=40.= Antiochus V. (Eu´pator), a boy of twelve years, came to the throne under the control of Lys´ias, the regent. But his father, when dying, had appointed him another guardian in the person of Philip, who returned to Antioch bearing the royal signet, while the young king and his minister were absent in Judæa. Lysias, on hearing this, hastened to make peace with Judas Maccabæus, and turned back to fight with Philip, whom he defeated and put to death. The Parthians, meanwhile, were overrunning the kingdom on the east; and the Romans, on the west, were harshly enforcing the terms of the treaty made by Antiochus the Great. Demetrius, the son of Seleucus Philopator, now escaped from Rome, and gained possession of the kingdom, after ordering the execution of both Eupator and his guardian. =41.= Demetrius I. spent some years in vain attempts to put down the Jewish rebellion. His armies were defeated by Judas Maccabæus, and the Romans entered into alliance with Judæa, which they now declared an independent kingdom. The Syrian king was no more successful in Cappadocia; and in Babylon, the satrap whom he had deposed set up an impostor, Alexander Balas, who claimed to be a son of Antiochus Epiphanes. Aided by the forces of Rome, Pergamus, Cappadocia, Egypt, and Judæa, this man conquered Demetrius and kept the kingdom five years. =42.= Alexander Balas proved unworthy of a crown, by leaving public affairs in the weak and incompetent hands of his favorite, Ammo´nius, while he abandoned himself to indolence and luxury. Demetrius Nica´tor, eldest son of the former king, encouraged by the contempt of the Syrians for the licentiousness of Alexander, landed in Cilicia and made war for the recovery of his kingdom. Ptolemy of Egypt, who had entered Syria with an army for the aid of his son-in-law, Alexander, became disgusted by his ingratitude and came over to the side of Demetrius. A battle near Antioch was decided in favor of the allies. Alexander fled into Arabia, where he was assassinated by some of his own officers. =43.= Demetrius II. (Nicator) ruled with such wanton cruelty as to alienate his subjects. One of them, Diod´otus Tryphon, set up a rival king in the person of Antiochus VI., a child two years of age, the son of Alexander Balas. After three or four years he removed this infant monarch and made himself king, with the aid of Judas Maccabæus. Demetrius, after fighting ineffectually seven years against his rivals in the west, left the regency of Syria to his wife, Cleopatra, while he turned against the Parthians, who had nearly conquered his eastern provinces. He was defeated and made prisoner by Arsaces VI., and remained ten years a captive, though he was treated with all the honors of royalty, and received a Parthian princess for his second wife.